Administering apparatus comprising a rotational block

ABSTRACT

An administering apparatus for delivering a dosage of product including a casing with a reservoir for the product, a conveying device, a dosage setting member mechanically coupled to the conveying device and a stopper for the dosage setting member. The conveying device is formed by a driven device and a drive device. The driven device, a piston rod in one embodiment, is mounted by the casing such that it performs a delivery movement in the form of a delivery stroke in an advancing direction along a translational axis to deliver a product dosage selected using the dosage setting member. The delivery movement of the driven device is effected with the drive device, the drive device and the driven device being coupled. The dosage setting member is coupled to the driven device such that a rotational dosing movement of the dosage setting member and the driven device relative to one another about the translational axis effects a translational dosing movement of the dosage setting member along the translational axis relative to the driven device and the casing. A translational stopper is provided to limit the movement of the dosage setting member. A rotational block is provided which permits the rotational dosing movement in a first rotational direction but blocks the rotational dosing movement in a second rotational direction.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of International PatentApplication No. PCT/CH02/00413, filed on Jul. 22, 2002, which claimspriority to German Application No. 101 63 358.9, filed on Dec. 21, 2002and German Application No. 201 12 501.3, filed on Jul. 30, 2001, thecontents of both are incorporated herein by reference in their entirety.

BACKGROUND

[0002] The invention relates to an administering apparatus foradministering a fluid product in doses. For example, the invention mayprovide an injection apparatus, such as an injection pen or asemi-disposable pen. Alternately, the invention may provide a dosingportion of an inhalation apparatus or an apparatus for oral ingestion orany other type of apparatus for administering a fluid product.

[0003] When administering a product, for example in medicalapplications, precise dosing of the product is important. In anadministering apparatus such as an injection apparatus, the product isgenerally dosed using a dosage setting member which engages a conveyingdevice. The dosage setting member selects the dosage of product to bedelivered and the conveying device delivers the dosage of product.Problems can arise with such apparatus when a dosing movement by thedosage setting member causes a response movement by the conveying devicedue to the engagement, in particular when such a response movementshould be avoided with regard to correct dosing.

SUMMARY

[0004] The present invention provides an administering apparatus fordelivering a dosage of product comprising a casing with a reservoir forthe product, a conveying device, a dosage setting member mechanicallycoupled to the conveying device and a stopper for the dosage settingmember. The conveying device is formed by a driven device and a drivedevice. The driven device is mounted by the casing such that it performsa delivery movement in the form of a delivery stroke in an advancingdirection along a translational axis to deliver a product dosageselected using the dosage setting member. The delivery movement of thedriven device is effected with the drive device, the drive device andthe driven device being coupled. The dosage setting member is coupled tothe driven device such that a rotational dosing movement of the dosagesetting member and the driven device relative to one another about thetranslational axis effects a translational dosing movement of the dosagesetting member along the translational axis relative to the drivendevice and the casing. A translational stopper is provided to limit themovement of the dosage setting member. A rotational block is providedwhich permits the rotational dosing movement in a first rotationaldirection but blocks the rotational dosing movement in a secondrotational direction.

[0005] The translational stopper limits the possible movement of thedosage setting member in one direction along the translational axis. Thedosage setting member is positioned generally opposite and axiallyfacing, in an axial end position, the translational stopper. The axialend position of the dosage setting member therefore corresponds eitherto a selectable maximum dosage or minimum dosage, which can be the zerodosage. Accordingly, the translational stopper can be a fronttranslational stopper or a rear translational stopper with respect tothe advancing direction.

[0006] If the dosage setting member performs a rotational dosingmovement, but is prevented from performing the translational dosingmovement resulting from being coupled with the driven device, the drivendevice performs an axial response movement if it is not otherwiseprevented. Preventing the response movement results either in damage tothe block or to the coupling between the driven device and the dosagesetting member. Such a situation can arise in particular when the dosagesetting member assumes the cited axial end position with respect to thetranslational stopper.

[0007] The rotational block acts in the axial end position of the dosagesetting member, and in the end position restricts the rotational dosingmovement of the dosage setting member to a first rotational direction,by blocking the rotational dosing movement in a second rotationaldirection. The rotational dosing movement which is blocked is that whichwould otherwise axially press the dosage setting member against thetranslational stopper. If the rotational dosing movement is performed inthe second rotational direction and the translational movement isblocked by the translational stopper, then, absent the rotational blockof the present invention, the dosage setting member would be pressedagainst the translational stopper with increasing force. The rotationalblock of the present invention prevents such a pressing force rising toan undesirable level or prevents it from arising at all.

[0008] The coupling between the driven device and the dosage settingmember may be realized by the driven device engaging the dosage settingmember. The coupling may operate to ensure that the driven device andthe dosage setting member may only be moved jointly in the advancingdirection. If the drive device acts on the dosage setting member, thedosage setting member slaves the driven device in the advancingdirection. If the drive device acts on the driven device, then thedriven device slaves the dosage setting member.

[0009] The rotational dosing movement effects a relative movementbetween the driven device and the dosage setting member. The couplingbetween the driven device and the dosage setting member may beconfigured as a screw joint. In one embodiment, the screw joint isformed by a direct threaded engagement, wherein the thread axis of theinterlocking threads of the drive device and the dosage setting membercoincides with the translational axis.

[0010] With respect to the advancing direction, the translationalstopper may be a front stopper. The front translational stopper limitsthe common movement of the driven device and the dosage setting memberin the advancing direction. Thus, the front translational stopper may bereferred to as the delivery stopper. Such a delivery stopper may beformed directly by the casing, may be rigidly connected to the casing,or may be immovably mounted by the casing.

[0011] Alternately, the translational stopper may be a rear stopper withrespect to the advancing direction. The rear translational stopperlimits the translational dosing movement of the dosage setting member.In accordance with a further embodiment, a delivery stopper and a reartranslational stopper may be provided in combination. The dosage settingmember is positioned axially opposite the respective translationalstopper in the two axial end positions, i.e. the dosage setting memberforms the counter stopper to both translational stoppers. While, in suchan embodiment, the delivery stopper limits the movement of the drivendevice and the dosage setting member by an actual contact, this is notrequired for the rear translational stopper. The rotational block inaccordance with the invention can be formed such that a translationaldosing movement of the dosage setting member, directed towards the reartranslational stopper is blocked before the dosage setting member canaxially push against the rear translational stopper. Providing a dosagesetting member opposite and axially facing a translational stopper, inits axial end position, permits a contact with a force in the axialdirection to occur, but causes a rotational block before contact canoccur. If the translational stopper is a rear stopper, the reartranslational stopper may be formed by the casing or axially andimmovably mounted by the casing. In another embodiment, the drive deviceforms a rear translational stopper, or a rear translational stopper ismounted by the drive device such that it cannot move axially relative tothe drive device.

[0012] In accordance with a further embodiment of the present invention,the dosage setting member cannot be rotated about the translationalaxis, relative to the casing. Instead the driven device may be rotatedabout the translational axis relative to the casing and the dosagesetting member, for performing the rotational dosing movement. Therotational block may be formed either between the dosage setting memberand a transfer member or between the dosage setting member and the drivedevice. The transfer member is connected, secured against rotating, tothe driven device and connected, axially immovably, to the casing. Thetransfer member may be formed by a blocking means which prevents thedriven device from moving counter to the advancing direction, relativeto the casing. In this embodiment, the drive device is connected,secured against rotating, to the driven device, but may be axially movedrelative to the driven device, to effect the rotational dosing movementand the delivery stroke.

[0013] In a second embodiment, the administering apparatus is configuredsuch that the dosage setting member can be rotated about thetranslational axis relative to the casing and the driven device, forperforming the rotational dosing movement, and the driven devicepreferably cannot be rotated relative to the casing. The rotationalblock, in such embodiment, is formed between the dosage setting memberand the casing.

[0014] The rotational block can be effected using a positive lock, africtional lock, or any other suitable lock. Using a positive block, therotational block comprises at least two rotational stoppers which formmutually facing stopper areas which reciprocally abut, for therotational direction of the rotational dosing movement which is to beblocked. The at least two cooperating rotational stoppers are formedsuch that they permit and preferably do not impede the rotational dosingmovement in the other rotational direction. The cooperating rotationalstoppers may be elastically flexible with respect to the rotationaldirection to be permitted. Preferably, however, the rotational stoppersand the transfer of the rotational dosing movement into thetranslational dosing movement, are adjusted to each other such that therotational stoppers cooperating for the purposes of blocking are movedapart sufficiently fast by the non-blocked rotational dosing movementthat they do not impede the rotational dosing movement to be permitted.This may be achieved by adjusting the axial extension of the cooperatingrotational stoppers to the transfer of the rotational dosing movementinto the translational dosing movement.

[0015] The rotational stoppers cooperating for blocking may be formed onsurface areas of the dosage setting member and the body. The rotationalstoppers may be formed radially facing one another. The dosage settingmember and the body, together with the dosage setting member, form thecooperating rotational stoppers.

[0016] In a further exemplary embodiment, the dosage setting member andthe translational stopper each form at least one rotational stopper onabutting areas which axially face one another. The at least tworotational stoppers thus formed abut one another in the axial endposition of the dosage setting member to block the rotational dosingmovement in one rotational direction. The cooperating rotationalstoppers may be formed as protrusions which protrude axially towards oneanother. It is also possible for only one of the cooperating rotationalstoppers to be formed as a protrusion, while the other is formed by arecess into which the protrusion protrudes in the axial end position ofthe dosage setting member.

[0017] In an embodiment of the administering apparatus wherein thedosage is selected in discrete increment, and the rotational dosingmovement occurs between discrete rotational angular positions, thecooperating rotational stoppers may be arranged such that they abutagainst one another or are situated just short of the position in whichthey abut one another. This position, abutment or just shy thereof, isachieved when the dosage setting member and the driven device assume thediscrete rotational angular positions relative to one another. In thisway, the undesirable rotational movement is blocked particularly early.If the cooperating rotational stoppers are formed by a protrusion and arecess, adjusting them in this way enables the protrusion to beaccommodated completely in the recess, in the axial end position of thedosage setting member.

[0018] If the product is delivered, using a piston which is advanced inthe reservoir in the advancing direction towards an outlet of thereservoir, then the piston and a piston rod form the driven device ofthe conveying device. The piston rod may be connected fixedly, i.e.permanently, to the piston. Further, the piston and the piston rod maybe formed as a unitary piece. The piston and the piston rod mayalternately be formed as separate components, a front end of the pistonrod pushing against a rear side of the piston to deliver the product.

[0019] The drive device may be configured as a dosing and drive devicewhich assists in selecting the dosage and can be moved axially andtranslationally relative to the casing and rotationally about thetranslational axis. The dosing and drive device may be connected eitherto the driven device or the dosage setting member, secured againstrotating with respect to the translational axis, preferably throughdirect engagement, in order to convert the rotational movement of thedosing and drive device directly into the rotational dosing movement.

[0020] In the embodiment described above, the driven device, the dosagesetting member and the dosing and drive device may be connected to oneanother by directly engaging each two or these components orsub-assemblies in pairs, without interposing transfer members.Alternately, interposing one or more transfer members may be done toconnect the dosage setting member and the dosing and drive device.

[0021] The dosing and drive device can operate manually,semi-automatically or fully automatically. For manual operation, boththe rotational dosing movement and the translational delivery movementare performed manually. For semi-automatic operation, one of either therotational dosing movement or the translational delivery movement isperformed manually with the other movement being performed using motorsor another type of force application, for example a spring force, whenthe user has triggered the corresponding movement using an activatinghandle. For full automatic operation, the dosing movement and thedelivery movement are performed using motors or another force, forexample a spring force. In this case, only the dosage is selectedmanually, for example using one or more buttons, and the deliverymovement is triggered by the user using a corresponding activatinghandle. In most embodiments, the administering apparatus of the presentinvention is equipped with a manual dosing and drive device, which isthen referred to as a dosing and activating device. Thus, whenever a“dosing and activating device” is mentioned, it is the manual embodimentwhich is being referred to. Where a dosing and drive device ismentioned, this is not intended to restrict the invention with respectto being manual, semi-automatic or fully automatic, but rather tocomprise each of these embodiments. The term “dosing and activatingmodule” is used in connection with all the embodiments of the dosing anddrive device.

[0022] The dosing and drive device can separately comprise a dosingelement which performs the dosing movement and a drive element whichperforms the delivery movement. Alternately, however, the dosingmovement and the delivery movement are performed by the same body of thedosing and drive device which is therefore also referred to in thefollowing as a dosing and drive element or dosing and activatingelement.

[0023] The product is preferably a fluid, particularly preferably aliquid, having a medical, therapeutic, diagnostic, pharmaceutical orcosmetic application. For example, the product may be insulin, a growthhormone or a thin or thick, pulpy food. The administering apparatus maybe employed in applications in which a user self-administers the producthim/herself, as is common in diabetes therapy. Further, use of theadministering apparatus by trained staff in treating patients is notexcluded.

[0024] In the case of an administering apparatus of the presentinvention comprising an injection apparatus, the product can beadministered using an injection cannula such as a nozzle for needle-freeinjections. The product may be injected or infused subcutaneously,venously, or also intramuscularly. Alternately, in an embodiment of theadministering apparatus of the present invention comprising aninhalation apparatus, the selected product dosage may be delivered fromthe reservoir into a chamber of the inhalation apparatus and vaporizedfor inhalation by a vaporizing means. Furthermore, oral ingestion oradministration via the esophagus may be used. Alternately, theadministering apparatus of the present invention may be configured forany other suitable administration to the patient.

[0025] The administering apparatus may configured as semi-disposable. Inthis case, the front casing section is a support for a reservoir modulewhich is disposed of or recycled once the reservoir has been emptied.The rear casing section is a support for a dosing and activating modulewhich may be repeatedly used in conjunction with a new reservoir module.As the reservoir module can also be treated separately as a disposablemodule, it is also a separate subject of the invention. Equally, asystem consisting of an administering apparatus and at least onereservoir module, which can replace the reservoir module of theapparatus once it has been used, forms a subject of the invention. Theduplex design of the administering apparatus, divided into a portionprovided for use only once and a portion provided for repeated use(semi-disposable), is advantageous for injection pens in particular, butis also useful for other administration such as via inhalation, oralingestion, or artificial feeding.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026]FIG. 1 illustrates two portions of a reservoir module inaccordance with a first embodiment of the present invention;

[0027]FIG. 2 illustrates the reservoir module formed by the two portionsof FIG. 1;

[0028]FIG. 3 illustrates a perspective view of an injection apparatusincluding the reservoir module of FIG. 2, in accordance with the firstembodiment, in a longitudinal section;

[0029]FIG. 4 illustrates a portion of the injection apparatus of FIG. 3;

[0030]FIGS. 5a-5 c illustrate a mechanism holder of the reservoirmodule, in a longitudinal section and two views;

[0031]FIGS. 6a-6 d illustrate a blocking device for a piston rod,mounted by the mechanism holder;

[0032]FIGS. 7a, 7 b illustrate a piston rod in a longitudinal sectionand a front view;

[0033]FIGS. 8a-8 c illustrates a latching block in a longitudinalsection, a view and a top view;

[0034]FIG. 9 illustrates a second embodiment of an injection apparatusof the present invention;

[0035]FIG. 10 illustrates the cross-section A-A of FIG. 9;

[0036]FIG. 11 illustrates the cross-section B-B of FIG. 9;

[0037]FIG. 12 illustrates the cross-section C-C of FIG. 9;

[0038]FIG. 13 illustrates the cross-section D-D of FIG. 9;

[0039]FIG. 14 illustrates a perspective view of the mechanism holder ofthe second embodiment of the present invention;

[0040]FIG. 15 illustrates the mechanism holder of FIG. 14, in a view;

[0041]FIG. 16 illustrates the cross-section A-A of FIG. 15;

[0042]FIG. 17 illustrates a perspective view of the dosage settingmember of the second embodiment;

[0043]FIG. 18 illustrates a longitudinal view of the dosage settingmember of FIG. 17;

[0044]FIG. 19 illustrates the dosage setting member of FIG. 17;

[0045]FIG. 20 illustrates a top view of the dosage setting member ofFIG. 17;

[0046]FIG. 21 illustrates a portion of the injection apparatus inaccordance with FIG. 3; and

[0047]FIG. 22 illustrates a portion of the injection apparatus inaccordance with FIG. 9.

DETAILED DESCRIPTION

[0048]FIGS. 1 and 2 illustrate a reservoir module 10 for use with anadministering apparatus of the present invention. As shown in FIG. 1,the reservoir module 10 is formed by a reservoir part 1 and a mechanismholder 3. The reservoir part 1 and the mechanism holder 3 may beconnected in any suitable manner to form the reservoir module 10. Apiston rod 4 protrudes on an end of the mechanism holder 3 facing awayfrom the reservoir part 1, into the mechanism holder 3. The piston rod 4is mounted by the mechanism holder 3 such that it can shift in anadvancing direction pointing along the longitudinal axis L of the pistonrod 4, towards a front end of the reservoir part 1 facing away from themechanism holder 3. The reservoir part 1 is substantially a hollowcylinder which has a circular cross-section and comprises a connectingregion at its front end for connecting to a needle holder for aninjection needle. The reservoir part 1 accommodates a reservoircontainer.

[0049]FIG. 3 illustrates an administering apparatus with the presentinvention comprising an injection apparatus. As shown, the reservoircontainer accommodated by the reservoir part 1 is an ampoule 2. Anoutlet at the front end of the ampoule 2 is sealed fluid-tight by amembrane. When a needle holder is fastened to the front end of thereservoir part 1, a rear portion of the injection needle pierces themembrane, such that a fluid connection between the tip of the hollowinjection needle and the reservoir 2 is established. A piston isaccommodated in the ampoule 2 such that it can shift in the advancingdirection towards the outlet formed at the front end of the ampoule 2.Shifting the piston in the advancing direction displaces product out ofthe ampoule 2 and delivers it through the outlet and the injectionneedle.

[0050] The piston is advanced by the piston rod 4 which pushes againstthe piston via its front end and thus moves the piston in the advancingdirection when advanced. The piston rod 4 is held by the mechanismholder 3 such that it can be moved in the advancing direction once acertain resistance, described below, has been overcome. The mechanismholder 3 further holds the piston rod 4 such that it cannot be movedcounter to the advancing direction. The piston rod 4 is prevented frommoving backwards, counter to the advancing direction, by a blockingdevice 8. The blocking device 8 is axially fixed by the mechanism holder3. As shown, the blocking device 8 is held in the mechanism holder 3such that it cannot be moved in and counter to the advancing direction.The mechanism holder 3 permits the blocking device 8 to be rotated aboutthe longitudinal axis L. The blocking device 8 also generates theresistance to be overcome to move forward.

[0051] The blocking device 8 is separately shown in FIGS. 6a-6 d. Theblocking device 8 is formed by an annular element which, rotatable aboutthe longitudinal axis L, abuts the mechanism holder 3 between twofacing, spaced collars 3 b. The mounting of the blocking device 8 in themechanism holder 3 can be seen in FIG. 5. The collars 3 b protruderadially inwards from an inner surface of the mechanism holder 3. Thecollars 3 b form a fixing means for axially fixing the blocking device8.

[0052] Returning to FIG. 3, a dosage setting member 9 is accommodated inthe mechanism holder 3. The dosage setting member 9, as shown, is formedas a threaded nut and is in threaded engagement with an outer thread ofthe piston rod 4. However, the dosage setting member 9 may be formed inany suitable manner. The dosage setting member 9 is secured againstrotating by the mechanism holder 3, but is guided such that it can moveaxially and linearly in and counter to the advancing direction. Thepiston rod 4 and the dosage setting member 9 together form a spindledrive for selecting the product dosage to be administered.

[0053] The ampoule holder 1 and the mechanism holder 3 are connected toone another, secured against rotating and shifting, and together formthe reservoir module 10 of the injection apparatus. The reservoir module10 comprises the piston rod 4 held by the mechanism holder 3 with theblocking device 8, and the dosage setting member 9. The ampoule holder 1and the mechanism holder 3 together form a front casing section of theinjection apparatus. A rear casing section 11 is connected to said frontcasing section 1′ in a positive lock. The rear casing section 11 formsthe support for a dosing and activating element 12 and, together withthe dosing and activating element 12 and, in some embodiments, parts ofa latching means and other parts, forms a dosing and activating module30 of the injection apparatus.

[0054] A plurality of components select the product dosage and activatethe administering apparatus. These include the dosage setting member 9,the piston rod 4 and the blocking device 8. Further included is a dosingand activating device, itself comprising a plurality of components. Thedosing and activating device comprises the dosing and activating element12 and a counting and indicating means 1. The counting and indicatingmeans 17 counts and optically indicates the selected product dosage. Ofcourse, the dosage may be indicated by the counting and indicating means17 in a manner other than optically, for example audibly. While thereservoir module 10 is designed as a disposable module, the dosing andactivating module 30 is intended for repeated use.

[0055] For selecting the product dosage, or dosing, the dosing andactivating element 12 can be rotated about the longitudinal axis L. Thedosing and activating element 12 is mounted by the rear casing section11 such that it can linearly shift along the longitudinal axis L, in andcounter to the advancing direction. The dosing and activating element 12is cylindrical and generally hollow. The dosing and activating element12 at least partially surrounds the piston rod 4 via a front section. Arear section of the dosing and activating element 12 protrudes outbeyond a rear end of the casing section 11. A rod-shaped dosing slavingmeans 13 is inserted into the dosing and activating element 12 from therear, as far as a collar of the dosing and activating element 12protruding radially inwards. At the rear end, a closure 14 is insertedinto the dosing and activating element 12, approximately as far as thedosing slaving means 13. The dosing slaving means 13 is axially fixedrelative to the dosing and activating element 12 between the radiallyprotruding collar of the dosing and activating element 12 and theclosure 14. The dosing slaving means 13 is also connected, securedagainst rotating, to the dosing and activating element 12. For dosing,the dosing slaving means 13 protrudes into the piston rod 4 from therear. The piston rod 4 is at least partially hollow to receive thedosing slaving means 13. As shown in FIG. 4, the piston rod 4 comprisesa connecting section 4 a which engages with the dosing slaving means 13such that the piston rod 4 and the dosing slaving means 13, andtherefore also the dosing and activating element 12, cannot be rotatedrelative to one another about the common longitudinal axis L, but can bemoved relative to each other along the longitudinal axis L, in andcounter to the advancing direction. For this purpose, the connectingsection 4 a is formed as a linear guide for the dosing slaving means 13.

[0056] A restoring means 16 elastically tenses the dosing and activatingelement 12 counter to the advancing direction, into the initial positionshown in FIGS. 3 and 4. In the initial position, the product can bedosed by rotating the dosing and activating element 12 about thelongitudinal axis L. From the initial position, the selected productdosage can be delivered by axially shifting the dosing and activatingelement 12. As shown, the restoring means 16 is formed by a spiralspring acting as a pressure spring, which is accommodated in an annulargap around the dosing and activating element 12. The restoring means 16is axially supported between a collar of the casing section 11protruding radially inwards and a collar of the dosing and activatingelement 12 facing opposite and protruding radially outwards. While aspiral spring is shown, the restoring means 16 may be configured in anysuitable manner.

[0057] The blocking device 8 fulfils a double function. It ensures viaits blocking elements 8 a that the piston rod 4 cannot be retracted,counter to the advancing direction, relative to the mechanism holder 3and relative to the piston accommodated in the ampoule 2. The blockingdevice 8 further functions as a brake. The blocking device 8 preventsthe piston rod 4 from moving forward during the dosing process in whichthe dosage setting member 9 is moved axially, counter to the advancingdirection, towards the dosing and activating element 12.

[0058] In the initial position shown in FIGS. 3 and 4, before dosing,the dosage setting member 9 abuts against a delivery stopper 3 c, shownin FIG. 5, formed by the mechanism holder 3, in the advancing direction.The piston rod 4 is in contract with the piston. For dosing, the dosagesetting member 9 is moved away from the delivery stopper 3 c towards thedosing and activating element 12 by the threaded engagement with thepiston rod 4 and the linear guide from the mechanism holder 3. Thisreduces a slight distance between a rear stopper area of the dosagesetting member 9 and a front stopper area of the dosing and activatingelement 12, but increases a slight distance between a front stopper areaof the dosage setting member 9 and the delivery stopper 3 c. Thedistance between the dosage setting member 9 and the delivery stopper 3c is the path length by which the dosage setting member 9 and, due tothe threaded engagement, the piston rod 4 are moved in the advancingdirection during the delivery movement of the dosing and activatingelement 12. The delivery stopper 3 c forms a front translationalstopper. During the delivery movement, the piston rod 4 pushes via itsfront end, which is formed by a plunger body connected to the piston rod4 such that it cannot move in or counter to the advancing direction,against the piston and pushes the piston forwards in the advancingdirection towards the outlet of the ampoule 2. The longitudinal axis Lforms the rotational and translational axis of the movements which areperformed to dose and deliver the product.

[0059] The distance between the dosage setting member 9 and the dosingand activating element 12 during the dosing process when the dosagesetting member 9 abuts against the delivery stopper 3 c corresponds tothe maximum product dosage which can be selected and delivered. Thestroke movement of the dosing and activating element 12 is of equallength for each delivery. Dosing merely sets the distance between thedosage setting member 9 and the delivery stopper 3 c and, thus, the pathlength which can be jointly traveled by the dosing and activatingelement 12 and the dosage setting member 9 during delivery. The dosingand activating element 12 forms a rear translational stopper 12 c whichlimits the translational dosing movement of the dosage setting member 9and thus defines the maximum delivery stroke which may be set.

[0060] The blocking device has a braking function and, therefore, abraking engagement exists between the piston rod 4 and the blockingdevice 8. FIGS. 6a through 6 d and FIGS. 7a and 7 b illustrate theblocking device 8 and its engagement with the piston rod 4. The blockingdevice 8 comprises two braking elements 8 b for the braking engagement,which, as shown, are each formed by an elastically flexing catch, likethe blocking elements 8 a before them. In the embodiment shown, theblocking device 8 is formed by an annular element from which fourelastic catches axially project on an abutting side. The catches arearranged in a uniform distribution over the circumference of the annularelement. Two mutually opposing catches form the blocking elements 8 aand the other two catches, likewise arranged mutually opposing, form thebraking elements 8 b. Alternately, the blocking device 8 may be formedin any suitable configuration. Likewise, if provided, each of theblocking elements 8 a and braking elements 8 b may be formed in anysuitable manner.

[0061] The piston rod 4 accordingly includes two returning blockingmeans 6, which are formed on opposing sides on the outer surface of thepiston rod 4 and extend in the longitudinal direction. The piston rod 4further includes two advancing braking means 7, which likewise extend inthe longitudinal direction of the piston rod 4 on mutually opposingsides. The thread of the piston rod 4 for threaded engagement of thepiston rod 4 with the dosage setting member 9 is formed by fourremaining threaded sections 5 which extend over almost the entire lengthof the piston rod 4. The returning blocking means 6 and the advancingbraking means 7 are each formed by a row of teeth. However, while theteeth of the returning blocking means 6 are formed as serrated teeth,narrowing in the advancing direction and comprising blocking areaspointing backwards and extending transverse to the advancing direction,the rows of teeth which form the advancing braking means 7 do notcomprise blocking areas pointing forwards having a comparable blockingeffect. The teeth of the advancing braking means 7 each exhibit a softertooth profile as compared to the returning blocking means 6. Of course,the returning blocking means 6 and the advancing braking means 7 mayalternately be formed in any suitable manner. The braking engagementbetween the blocking device 8 and the advancing braking means 7 of thepiston rod 4 is not intended to prevent the piston rod 4 from beingadvanced, but merely to make it more difficult, thereby ensuring thatthe piston rod 4 is not moved in the advancing direction during dosing.The front sides of the teeth of the advancing braking means 7 and therear sides of the braking elements 8 b, which contact the front sides ofthe teeth of the advancing braking means 7, are configured such that athreshold force which is not reached during dosing has to be exceeded toovercome the braking engagement. This threshold force exceeds the forcerequired to move the teeth of the returning blocking means 6 over theblocking elements 8 a in the advancing direction. The threshold force ispreferably at least twice as large as the initial frictional forcebetween the returning blocking means 6 and the blocking elements 8 a.The frictional force between the latter increases gradually between twoconsecutive blocking engagements during the advancing movement. Thethreshold force of the braking engagement, by contrast, has to beapplied from one blocking engagement to the next, immediately at thebeginning of the advancing movement, in each blocking engagement.Regardless, the threshold force should not, be so large as to distractthe user during delivery.

[0062] An undesired advancing movement by the piston rod responsive tothe movement by the dosage setting member 9 when selecting the dosagemay be prevented by the blocking engagement of the blocking device 8alone. However, such a movement is more reliably prevented inconjunction with the braking engagement than by relying the blockingengagement alone.

[0063] The connection between the reservoir module 10 and the dosing andactivating module 30 is a positive lock. A latching engagement existsbetween the mechanism holder 3 and the casing section 11 which preventsrelative movement in the axial direction. Beyond the latchingengagement, the front casing section 1′ and the rear casing section 11are guided axially and linearly directly onto one another to preventrelative rotating when connected. The axial guides 3 d of the mechanismholder 3, which together with one or more corresponding engagementelements of the rear casing section 11 form the linear guide, can beseen in FIGS. 5a-5 c. As shown, the axial guides 3 d are formed by guideareas on guide ribs. The axial guides 3 d may alternately be formed byguide areas in axially extending recesses, thus forming axial guidechannels. The guide ribs are axially tapered, such that insertionfunnels leading into the guide channels are formed for the one or moreengagement elements of the rear casing section 11. To better center thecasing sections 1′ and 11 at the beginning of connecting, the guide ribsare also tapered in the radial direction. The one or more engagementelements of the rear casing section 11 may be formed like the axialguides 3 d on the inner surface area of the rear casing section 11.

[0064] A latching engagement exists between a first, female latchingelement 3 a of the mechanism holder 3 and a latching ring 20 which isconnected to the rear casing section 11 such that it can move radiallybut not axially. The latching ring 20 forms a second, male latchingelement 21 which radially engages directly with the first latchingelement 3 a. A lock/latch connection exists between the first latchingelement 3 a and the second latching element 21 which prevents thereservoir module 10 and the dosing and activating module 30 from movingaxially relative to one another.

[0065] Returning to FIGS. 3 and 4, the second latching element 21 inlatching engagement with the first latching element 3 a. The firstlatching element 3 a is formed by an annular stay and a groove whichruns around the outer surface of the mechanism holder 3. The annularstay forms a rear side wall of the groove. The second latching element21 is formed by a cam which protrudes radially inwards from the innersurface of the latching ring 20 and which in the latching engagement ispushed radially inwards over an inner surface area of the rear casingsection 11, protruding into the accommodating latching element 3 a, by arestoring means 24. The latching ring 20 is supported in the radialdirection on an inner surface area formed by the rear casing section 11,by the restoring means 24, such that the restoring means 24 pushesagainst the outer surface of the latching ring 20 roughly in a radialextension of the latching element 21. The latching ring 20 surrounds themechanism holder 3 and can be moved radially back and forth against therestoring force of the restoring means 24, such that the second latchingelement 21 can be moved in and out of latching engagement with the firstlatching element 3 a. The rear casing section 11 forms a tight slidingguide for the radial movement of the latching ring 20. On its sideradially opposite the latching element 21, the latching ring 20 forms anunlatching button 22. To radially guide the restoring means 24, formedas a pressure spring, a guide cam projects radially from the outersurface area of the latching ring 20 facing away from the latchingelement 21.

[0066] Two blocking cams 23 are provided to prevent a radial movement ofthe second latching element 21. Such radial movement could otherwiseresult in the latching engagement being released. The blocking cams 23press radially outwards against a latching block 25 and project from theouter surface area of the latching ring 20, in the circumferentialdirection on both sides of said guide cam and axially behind the guidecam. The blocking cams 23 thus abut against the latching block 25. Thelatching engagement between the latching elements 3 a and 21 is thussecured by the latching block 25. The latching engagement is secured ineach position of the dosing and activating element 12, except for areleasing position which the dosing and activating element 12 assumes atthe end of its delivery movement. The releasing position coincides withthe foremost shifting position of the dosing and activating element 12when it abuts the dosage setting member 9 during its delivery movementand the dosage setting member 9 abuts against the delivery stopper 3 cof the mechanism holder 3. Providing the dosing and activating module 30is not yet connected to the reservoir module, a mechanical stopper forthe dosing and activating element 12 is formed by a stopper element 31of the dosing and activating device. In the embodiment shown, a resetholder ring which resets the indicator 17 forms the stopper element 31.The dosing and activating element 12 abutting against the stopperelement 31 defines the releasing position of the dosing and activatingelement 12. The releasing position defined by the stopper element 31corresponds to that defined by the dosage setting member 9 abutting thedelivery stopper 3 c.

[0067]FIGS. 8a through 8 c illustrate the latching block 25. As shown,the latching block 25 is formed by a blocking slider as a unitary piece.The latching block 25 comprises a plate-shaped main body which extendsaxially when assembled, as for example shown in FIG. 4. At one end, astay 26 projects at approximately right angles from the main body. Whenassembled, the stay 26 extends radially approximately as far as thedosing and activating element 12. The stay 26 fastens the latching block25 to the dosing and activating element 12 which, for this purpose,comprises two annular stays formed axially spaced on an outer surfacearea. The two annular stays form the slaving means 15 a and 15 b. Thefront slaving means 15 a also forms the support collar for the restoringmeans 16. The latching block 25 is tightly enclosed axially on bothsides by the two slaving means 15 a and 15 b. The latching block 25protrudes into the annular space formed between the two slaving means 15a and 15 b via its stay 26.

[0068] At a front end facing away from the stay 26, the main body of thelatching block 25 is provided with an axial recess 27 which is opentowards the front end of the latching block 25. Blocking tongues 28extending axially on both sides of the recess 27 are thus formed. Theblocking cams 23 of the latching ring 20 are arranged such that each ofthe blocking cams 23 pushes against one of the blocking tongues 28,providing the dosing and activating element 12 does not assume thereleasing position. When the latching block 25 moves axially, therestoring means 24 for the latching element 21 extends through the axialrecess 27. Indentation recesses 29 are furthermore formed in the mainbody of the latching block 25, and define the releasing position of thedosing and activating element 12. One indentation recess 29 is providedfor each of the blocking cams 23. The position of the indentationrecesses 29 is selected such that they only overlap the blocking cams23, and thus allow the blocking cams 23 to be inserted, when the dosingand activating element 12 has been advanced into its releasing position.

[0069] Of course, in the arrangement shown, a single blocking cam 23could also be provided and the latching block 25 accordingly compriseonly one indentation recess 29 and as well as only one blocking tongue28. The latching block 25 may alternately be produced together with thedosing and activating element 12 as a unitary piece. Further, any othersuitable configuration for the latching block 25 may be used. Withrespect to the installation length of the latching block 25, thelatching block 25 is supported, on its outer side facing away from thelatching element 21, on an inner surface area of the casing 11. Thisincreases the stability of securing the latching engagement. The casing11 preferably forms an axial guide for the latching block 25.

[0070] The functionality of the injection apparatus is described in thefollowing, wherein it is assumed that a new reservoir module 10 and adosing and activating module 30 which has already been used at leastonce are assembled and a product is then delivered for the first time.

[0071] The dosing and activating module 30 and the new reservoir module10 are aligned axially with respect to one another, such that their twolongitudinal axes are flush with one another. The reservoir module 10 isinserted via its rear end into the casing 11, which is open to thefront, of the dosing and activating module 30. This centers the casingsection 1′ and the casing section 11 on the tapered ends of the guideribs 3 d of the mechanism holder 3. The two casing sections are guidedaxially and linearly onto one another in a rotational angular positionpre-set by the linear guide, until the casing sections 1′ and 11 assumea connecting end position in which the latching engagement of thelatching elements 3 a and 21 can be established.

[0072] The dosing and activating element 12 is locked in pre-setrotational angular positions relative to the rear casing section 11. Thelinear guide of the casing sections 1′ and 11 and the rotational angularlocking positions of the dosing and activating element 12 are adjustedto one another such that the engagement, secured against rotating,between the dosing and activating element 12 and the piston rod 4 isestablished in each locking position of the dosing and activatingelement 12 and each rotational angular position in which the casingsections 1′ and 11 are linearly guided onto one another.

[0073] If the dosing and activating element 12 is situated in an axialposition relative to the casing section 11 which is behind the releasingposition, the latching element 21 is held in its radially innermostposition by the latching block 25. In this position of the latchingelement 21, the dosing and activating module 30 and the reservoir module10 cannot be slid onto each other up to the connecting end position andtherefore also cannot be connected to one another, as the annular stayformed on the outer surface of the mechanism holder 3, which forms apart of the first latching element 3 a, comes to rest abutting againstthe second latching element 21 first.

[0074] The annular stay may be reduced to a short radial protrusion inthe tangential direction, if it is ensured that the casing sections 1′and 11 can only be assembled in the rotational angular position in whichsuch a protrusion and the second latching element 21 come to rest in anaxial flush. The annular stay or radial protrusion may also form thefirst latching element 3 a. The first latching element 3 a allows theconnection between the reservoir module 10 and the dosing and activatingmodule 30 to be established only when the dosing and activating element12 assumes its releasing position. If this condition is fulfilled, thedosing and activating element 12 ensures, when the connection betweenthe reservoir module 10 and the dosing and activating module 30 isestablished, that the dosage setting member 9 is situated in its dosingzero position, abutting the delivery stopper 3 c of the mechanism holder3.

[0075] To fulfill the above-described condition, wherein the dosing andactivating element 12 assumes its released position, the user pushes thedosing and activating element 12 axially forwards relative to the rearcasing section 11 approximately as far as the releasing position. Inthis relative position between the rear casing section 11 and the dosingand activating element 12, the blocking cams 23 may be moved into theindentation recesses 29 of the latching block 25. The user therefore notonly pushes the dosing and activating element 12 but also pushes thesecond latching element 21 out of latching engagement by using theunlatching button 22. The reservoir module 10 may then be moved axiallyover the annular stay of the first latching element 3 a and insertedfurther into the rear casing section 11. The user can release theunlatching button 22. When the second latching element 21 overlaps thefirst latching element 3 a, the second latching element 21 snaps intothe accommodating first latching element 3 a due to the force of therestoring means 24, such that the latching engagement is established.The reservoir module 10 and the dosing and activating module 30 are thenconnected to each other in a defined way with respect to the position ofthe dosage setting member 9 and the piston rod 4. If the dosage settingmember 9 still exhibited a slight distance from the delivery stopper 3 cbefore the latching engagement is established, this distance isgenerally eliminated by the action of the dosing and activating element12 required to establish the connection. A resultant delivery of productcan be accepted for priming the injection needle. This preferably resetsthe counting and indicating means 17 to zero.

[0076] In the defined initial, the user can dose the product. Theproduct is dosed by rotating the dosing and activating element 12 aboutthe longitudinal axis L and relative to the casing section 11. As thedosing slaving means 13 is connected to the dosing and activatingelement 12, secured against rotating, and engages with the piston rod 4,secured against rotating, the dosing and activating element 12 slavesthe piston rod 4 during its rotational dosing movement. Due to thethreaded engagement between the piston rod 4 and the dosage settingmember 9 and the linear guide of the dosage setting member 9 by themechanism holder 3, the dosage setting member 9 performs an axial,translational dosing movement, pre-set by the thread pitch of thereciprocal threaded engagement, towards the dosing and activatingelement 12. The rear translational stopper 12 c formed by the dosing andactivating element 12 limits the translational dosing movement of thedosage setting member 9 and defines the maximum delivery stroke whichmay be set.

[0077] The counting and indicating means 17 counts the dosage unitscorresponding to the rotational angular position of the dosing andactivating element 12 and indicates it optically.

[0078] Once the desired product dosage has been selected, the dosingprocess is completed. The selected product dosage is delivered by thedelivery movement, pointing in the advancing direction of the piston, ofthe dosing and activating element 12. During the delivery movement, thedosing and activating element 12 abuts against the dosage setting member9 and slaves it. When the dosage setting member 9 abuts against thedelivery stopper 3 c of the mechanism holder 3 during the deliverymovement, the delivery movements of the dosing and activating element 12and the delivery of product are completed. Once the user releases thedosing and activating element 12, the dosing and activating element 12is moved counter to the advancing direction and returned to a newinitial position for dosing and delivering the product again, by therestoring means 16. The counting and indicating means 17 is preferablycoupled to the dosing and activating element 12 such that it resets tozero after delivery of the product. Further, the counting and indicatingmeans 17 may be configured such that it counts and indicates the totalproduct amount already delivered and thus the residue product amountremaining in the ampoule 2.

[0079] To detach the reservoir module 10 from the dosing and activatingmodule 30, the dosing and activating element 12 is advanced to thereleasing position, i.e. until it abuts against the dosage settingmember 9. The user releases the latching engagement by pushing theunlatching button 22 and separates the reservoir module 10 from thedosing and activating module 30.

[0080] FIGS. 9 to 13 illustrate a second embodiment of an injectionapparatus in accordance with an administering apparatus of the presentinvention. The injection apparatus of the second embodiment correspondswith that of the first embodiment with respect to the latch and latchingblock 25, such that reference is made in this regard to the descriptionof the first embodiment. The latching block 25 of the second embodimentreflects that of the first embodiment with respect to all its functionaldetails. The same applies to the latching elements 3 a and 21.

[0081] The latching ring 20 and the position of the blocking cams 23relative to the latching element 21 and relative to the latching block25 in the initial state of the apparatus is shown in the cross-sectionsof FIGS. 10, 11 and 12, to which reference is made in this regard, alsoas representative for the first embodiment.

[0082] The injection apparatus of the second embodiment differs from thefirst embodiment in the engagement and the progression of movement ofthe components involved in dosing. Furthermore, the mechanism holder, inaddition to the functions of the mechanism holder of the firstembodiment, positions the dosage setting member in discrete rotationalangular positions which may be changed relative to the mechanism holder,for the purpose of dosing. The blocking means of the second embodiment,by contrast, is embodied more simply than that of the first embodiment.For the most part, the differences as compared to the first embodimentwill be described in the following, wherein for components which areidentical in their basic function to the components of the same name inthe first embodiment but differ in details, numbers in the thirties withthe same end digit, or exactly the same reference numerals as in thefirst embodiment, are used. Where no statements are made regarding thesecond embodiment, the corresponding statements regarding the firstembodiment shall apply.

[0083] In the second embodiment, the dosing and activating element 32,which can be moved axially and linearly relative to the rear casingsection 11 and rotated about the longitudinal axis L, is connected tothe dosage setting member 39, secured against rotating. The dosing andactivating element 32 and the dosage setting member 39 can be moved inand counter to the advancing direction, relative to one another andrelative to casing sections 1′ and 11. The piston rod 4 is held by amechanism holder 3, secured against rotating. In cooperation withblocking elements of the blocking device 38, formed on the mechanismholder 3 as a unitary piece, the returning blocking means 6, which isfunctionally identical to the first embodiment, prevents the piston rod4 from moving counter to the advancing direction, but allows it to movein the advancing direction. The blocking elements forms both thereturning block and the rotational block for the piston rod 4.Furthermore, as previously in the first embodiment, the dosing andactivating element 32 forms a sliding guide for the piston rod 4.

[0084] During dosing, the dosing and activating element 32 performs thesame rotational dosing movement as the dosing and activating element 12of the first embodiment. However, as the engagement is secured againstrotating, the dosage setting member 39 is slaved during the rotationaldosing movement. The threaded engagement between the piston rod 4 andthe dosage setting member 39 is again comparable to that of the firstembodiment. Due to the rotational dosing movement and the threadedengagement with the piston rod 4, a stopper 39 c formed by the dosagesetting member 39 is moved, during dosing, counter to the advancingdirection, towards a front end of the dosing and activating element 32.As opposed to the first embodiment, the dosage setting member 39 thuscompletes a rotational dosing movement and a translational dosingmovement relative to the front casing section during dosing, while thepiston rod 4 remains stationary. Once dosing has been completed, thedelivery movement of the dosing and activating element 32 advances thepiston rod 4 by the path length which corresponds to the slight distancebetween a stopper area of the dosage setting member 39 and the deliverystopper 3 c of the mechanism holder 3, set by the dosing.

[0085] The translational dosing movement of the dosage setting member 39is limited counter to the advancing direction by a rear translationalstopper 11 c which is formed directly by the rear casing section 11. Therotational and translational axis of the components involved in dosingand delivering the product forms the longitudinal axis L.

[0086] As in the first embodiment, the front casing section 1′ forms asliding guide for the dosage setting member 39. In order to form thesliding guide, an inner surface area of the mechanism holder 3 and anouter surface area of the dosage setting member 39 are in slidingcontact with each other. The dosing and activating element 32 engageswith an inner surface area of the dosage setting member 39, to form theconnection, secured against rotating, between the dosage setting member39 and the dosing and activating element 32.

[0087] In the second embodiment, the piston rod 4 comprises no brakingmeans of its own beyond the returning blocking means 6. Rather, thefront sides of the serrated teeth of the returning blocking means 6 alsoform the braking means. The piston rod 4 of the second embodiment can,however, be replaced by the piston rod 4 of the first embodiment.Accordingly, the mechanism holder 3 of the second embodiment may form atleast one braking element, and preferably both braking elements, of thefirst embodiment.

[0088] FIGS. 14 to 16 illustrate the mechanism holder 3 of the secondembodiment in a perspective representation, a side view and in thecross-section A-A indicated in the side view. As in the firstembodiment, the mechanism holder 3 is embodied as a unitary sleeve part,for example as a plastic injection molded part. It comprises a bulge 3 eon the outer surface of a front sleeve section. The front sleeve sectionis plugged into the reservoir part 1 and locked non-detachably, at leastfor the user, to the reservoir part 1 by the bulge 3 e.

[0089] The latching element 3 a is formed on a middle sleeve section ofthe mechanism holder 3, as in the first embodiment. A rear sleevesection, connected to the latching element 3 a, forms a plurality ofaxial guides 3 d on its outer circumference. The axial guides 3 d areformed by guide ribs which protrude radially on the outer circumferenceof the rear sleeve section. The axial guides are formed by the axiallyextending, straight side walls of said guide ribs, such that, as in thefirst embodiment, axial guiding channels are obtained. The guide ribsprotrude from the middle sleeve section, approximately as far as therear end of the mechanism holder 3, where they taper axially. The axialguide 3 d linearly guides the rear casing section 11 when the reservoirmodule 10 is connected to the dosing and activating module 30. As can beseen in FIGS. 9 and 11, engagement elements 11 d project radiallyinwards from the inner surface area of the rear casing section 11. Oneengagement element 11 d protrudes into each of the axial guides 3 d andis linearly guided by the axial guide 3 d when the front casing section1′ and the rear casing section 11 are slid into one another. Thisrestricts relative rotating between the front casing section 1′ and therear casing section 11 during engagement, secured against rotating,between the dosing and activating element 32 and the dosage settingmember 39.

[0090] As the guide ribs taper axially at their rear ends, and the guidechannels are thus widened into insertion funnels, centering between thefront casing section 1′ and the rear casing section 11, for the purposeof connecting, is simplified. The guide ribs also taper at their endsradially with respect to the surface area of the mechanism holder 3,which simplifies centering the casing sections 1′ and 11 into arotational angular position pre-set by the axial guide 3 d, relative toone another.

[0091] Just as the front casing section 1′ and the rear casing section11 are prevented from rotating relative to one another duringconnection, the dosage setting member 39 is also fixed with respect toits rotational angular position relative to the front casing section 1′.The dosage setting member 39 is detachably fixed to allow the rotationalmovement of the dosage setting member 39 necessary for dosing. To enablethe dosing movement of the dosage setting member 39 but prevent anundesired dosing movement by establishing the connection between thefront casing section 1′ and the rear casing section 11, the dosagesetting member 39 is fixed by the mechanism holder 3 in discreterotational angular positions, by a releasable locking connection.

[0092] FIGS. 17 to 20 show individual representations of the dosagesetting member 39. For forming the locking connection, a number oflocking recesses 39 g are formed on the outer surface area of the dosagesetting member 39, distributed in generally regular intervals over thecircumference of the dosage setting member 39. Each of the lockingrecesses 39 g is formed by a straight, axially extending furrow having arounded contour running in its cross-section. Of course, the lockingrecesses 39 g may alternately be formed in any suitable manner.

[0093] Returning to FIGS. 15 and 16, the mechanism holder 3 is providedwith two locking projections 3 g. The two locking projections 3 gproject radially inwards from an inner surface area of the mechanismholder 3 in the rear sleeve section of the mechanism holder 3. The twolocking projections 3 g, as shown, are arranged diametrically opposed toone another. The respective surface region of the mechanism holder 3, onwhich one of the locking projections 3 g is formed, forms a springelement 3 f which is elastically flexible in the radially direction. Dueto the elastic flexibility and the rounded shape of the lockingprojections 3 g, in conjunction with the rounded profile of the lockingrecesses 39 g, the locking engagement between the locking projections 3g and the opposing locking recesses 39 g may be released. Releasing thelocking engagement between the locking projections 3 g and the opposinglocking recesses 30 g allows the dosage to be selected. The lockingengagement is designed, however, such that the dosage setting member 39is rotationally angularly fixed and undesired dosing movement of thedosage setting member 39 is prevented when the front casing section 1′and the rear casing section 11 are connected and when the rotationalcoupling between the dosing and activating element 32 and the dosagesetting member 39 is established. The locking connection between themechanism holder 3 and the dosage setting member 39 has the advantageousside effect of a tactile signal during dosing. To maintain theelasticity of the spring element 3 f, the rear sleeve section of themechanism holder 3 is cut away in the surface region, such that thespring element 3 f is maintained as an annular segment extending in thecircumferential direction which is axially free on both sides.

[0094] Returning to FIGS. 17 through 20, axial guides 39 d are providedfor the engagement, secured against rotating, between the dosage settingmember 39 and the dosing and activating element 32. The dosing andactivating element 32 is provided with at least one engagement element,in order to obtain the axial linear guide, i.e. the rotational block,between the dosing and activating element 32 and the dosage settingmember 39. The axial guides 39 d are again guide channels formed by anumber of guide ribs extending axially in a straight line. Each of theguide ribs tapers axially and radially at its rear end facing the dosingand activating element 32, thus simplifying centering between the dosingand activating element 32 and the dosage setting member 39, when theengagement, secured against rotating, is established. The same design istherefore used for the axial linear guide of the dosage setting member39 and the dosing and activating element 32 as for the axial linearguide of the casing sections 1′ and 11.

[0095] The dosing setting member 39 is further provided with a dosingthread 39 a and a delivery stopper 39 c. Two rotational blocks areprovided for the dosage setting member 39 which are active in the twoaxial end positions of the dosage setting member 39. Reference isadditionally made in this regard to FIG. 22.

[0096] To prevent retraction of the piston rod 4 in response to arotational dosing movement by the dosage setting member 39, rotationalstoppers 39 h are formed at a front end of the dosage setting member 39.In the front position, which the dosage setting member 39 assumesdirectly after the product is delivered or before the dosage isselected, the rotational stoppers 39 h engage with rotational counterstoppers 3 h formed on the mechanism holder 3 (FIG. 16). The rotationalstoppers 39 h axially project from a front abutting side of the dosagesetting member 39, and the rotational counter stoppers 3 h protrude froman axially facing abutting area of the mechanism holder 3 forming thedelivery stopper 3 c, axially opposed to the rotational stoppers 39 h.The engagement between the rotational stoppers 39 h and the rotationalcounter stoppers 3 h is such that it allows a rotational dosing movementin a rotational direction, which causes a translational dosing movementof the dosage setting member 39 directed away from the delivery stopper3 c, but prevents a rotational dosing movement in the oppositerotational direction, in the front axial end position.

[0097] A further pair of rotational stoppers and rotational counterstoppers is provided, which are formed and cooperate in basically thesame way as the stoppers 3 h and 39 h. The second pair of rotationalstoppers are rotational stoppers 39i which axially project from a rearabutting area of the dosage setting member 39, and rotational counterstoppers 11 i which axially protrude from the facing stopper abuttingarea of the rear translational stopper 11 c towards the dosage settingmember 39. The rotational counter stoppers 11 i cannot be seen in FIG. 9due to their small dimensions. In the rear end position, the rear pairof rotational stoppers 11 i/39 i prevents the the piston rod 4 frombeing moved in the advancing direction in response to a dosing movementby the dosage setting member 39, directed against the rear translationalstopper 11 c.

[0098] The height, or axial length, of all the rotational stoppers 3 h,39 h, 11 i and 39 i is adjusted to the thread pitch of the engageddosing thread of the piston rod 4 and the dosage setting member 39. Therotational stoppers are axially sufficiently short that the rotationaldosing movement which moves the dosage setting member 39 away from therespective translational stopper 3 c or 11 c is not impeded.

[0099] When assembling the components of the reservoir module 10, thedosage setting member 39 is screwed onto the piston rod 4 as far as apre-set axial position, as may be seen from FIG. 9. The piston rod 4,together with the screwed-on dosage setting member 39, is then insertedinto the mechanism holder 3 from behind, until its blocking device 38comes into blocking engagement with the returning blocking means 6 ofthe piston rod 4 and the engagement, secured against rotating, betweenthe rotational stoppers 39 h of the dosage setting member 39 androtational counter stoppers of the mechanism holder 3 is established.During insertion into the mechanism holder 3, the dosage setting member39 is axially and linearly guided by the mechanism holder 3 via thelocking engagement between the locking projections 3 g and the lockingrecesses 39 g, until the dosage setting member 39 abuts the deliverystopper 3 c of the mechanism holder 3. In this front end position of thedosage setting member 39 relative to the mechanism holder 3, theengagement, secured against rotating, between the rotational stoppers 3h and 39 h is established. In this state, the mechanism holder 3 and areservoir part 1, already fitted with a reservoir, are connected to eachother.

[0100] In a following step, the rear casing section 11 of the assembleddosing and activating module 30 is slid onto the mechanism holder 3,wherein the mechanism holder 3 and the rear casing section 11 can becentered with respect to each other due to the axial guides 3 d and theengagement elements 11 d of the rear casing section 11. Once centered,the mechanism holder 3 and the rear casing section 11 are axially andlinearly guided onto one another due to the guide engagement. In thecourse of sliding the rear casing section 11 onto the mechanism holder3, the dosing and activating element 32 comes into engagement, securedagainst rotating, with the dosage setting member 39, wherein centeringis also possible, using a linear guide corresponding to the axial guides3 d and the engagement elements 11 d.

[0101] The dosing and activating element 32 is in locking engagementwith the rear casing section in discrete rotational angular lockingpositions and in the locking engagement, i.e. in the respectiverotational angular locking position, is axially and linearly guided. Therotational angular difference between two consecutive rotational angularlocking positions corresponds to one dosage unit. The linear guidebetween the mechanism holder 3 and the rear casing section 11 and thediscrete rotational angular positions of the dosage setting member 39relative to the mechanism holder 3 (locking projections 3 g and lockingrecesses 39 g) and the rotational angular locking positions of thedosing and activating element 32 relative to the rear casing section 11are adjusted to one another such that the two casing sections 1′ and 11are slid linearly over one another in a rotational angular position.Thus, the dosage setting member 39 and the dosing and activating element32 are also aligned relative to one another for their engagement,secured against rotating, such that there is no relative rotatingbetween the components involved in dosing while the reservoir module 10is connected to the dosing and activating module 30.

[0102] With respect to the other details of assembling, in particular ofestablishing the latching engagement, and of the functionality of theinjection apparatus in accordance with the second embodiment, referenceis made to the description of first embodiment.

[0103] As shown in FIG. 21, rotational blocks may also be provided inthe injection apparatus of the first embodiment. The rotational blocksprevent undesired response movements by the piston rod 4 in the twoaxial end positions of the dosage setting member 9 of the firstembodiment. The two rotational blocks are formed in the same way as therotational blocks of the second embodiment. However, the rotationalcounter stoppers which in the second embodiment are formed on the casingsections 1′ and 11 are formed in the first embodiment by the blockingdevice 8 and the dosing and activating element 12. Thus, a number ofrotational stoppers 8 h are formed on the abutting side of the blockingdevice 8 axially facing the dosage setting member 9 and axially protrudetowards the dosage setting member 9. As the blocking device 8 is axiallyand immovably mounted by the front casing section 1′ and connected,secured against rotating, to the piston rod 4, a rotational block forthe rotational dosing movement between the piston rod 4 and the dosagesetting member 9 is also obtained, via the front pair of rotationalstoppers 8 h/9 h. A second pair of rotational stoppers is formed betweenthe dosage setting member 9 and the rear translational stopper 12 c. Asin the second embodiment, a number of rotational stoppers 12 i protrudeaxially towards the dosage setting member 9 from the abutting area ofthe translational stopper 12 c axially facing the dosage setting member9. As in the second embodiment, the dosage setting member 9 is providedon its rear side with rotational stoppers 9 i which, in the rear axialend position of the dosage setting member 9, engage with the rotationalstoppers 12 i. In the rear axial end position of the dosage settingmember 9, the rear pair of rotational stoppers 9 i/12 i only allows therotational dosing movement which causes a translational dosing movementof the dosage setting member 9 in the advancing direction.

[0104] In the foregoing description, embodiments of the invention,including preferred embodiments, have been presented for the purpose ofillustration and description. They are not intended to be exhaustive orto limit the invention to the precise form disclosed. Obviousmodifications or variations are possible in light of the aboveteachings. The embodiments were chosen and described to provide the bestillustration of the principals of the invention and its practicalapplication, and to enable one of ordinary skill in the art to utilizethe invention in various embodiments and with various modifications asare suited to the particular use contemplated. All such modificationsand variations are within the scope of the invention as determined bythe appended claims when interpreted in accordance with the breadth theyare fairly, legally, and equitably entitled.

1. An administering apparatus for administering a fluid product indoses, the administering apparatus comprising: a) a casing including areservoir for the product; b) a driven device for performing a deliverystroke in an advancing direction along a translational axis to deliver aproduct dosage; c) a drive device for performing a delivery movement todeliver the product dosage; d) a dosage setting member coupled to thedriven device such that a rotational dosing movement, performed by thedosage setting member and the driven device about the translationalaxis, causes an axial translational dosing movement of the dosagesetting member relative to the driven device and the casing; e) atranslational stopper positioned opposite and axially facing the dosagesetting member, in an axial end position of the dosage setting member;and f) a rotational block which, in the axial end position of the dosagesetting member, permits the rotational dosing movement in a firstrotational direction and blocks the rotational dosing movement in asecond rotational direction.
 2. The administering apparatus of claim 1,wherein the rotational block prevents the dosage setting member frombeing pressed axially against the translational stopper by therotational dosing movement.
 3. The administering apparatus of claim 1,wherein the rotational block comprises at least one first rotationalstopper and at least one second rotational stopper, the first rotationalstopper and the second rotational stopper abutting against one anotherin the end position of the dosage setting member, wherein the at leastone first rotational stopper is mounted, secured against rotating, bythe dosage setting member and the at least one second rotational stopperis mounted, secured against rotating, by the casing.
 4. Theadministering apparatus of claim 1, wherein the rotational blockcomprises at least one first rotational stopper and at least one secondrotational stopper, the first rotational stopper and the secondrotational stopper abutting against one another in the end position ofthe dosage setting member, wherein the at least one first rotationalstopper is formed, secured against rotating, by the dosage settingmember and the at least one second rotational stopper is formed, securedagainst rotating, by the casing.
 5. The administering apparatus of claim1, wherein the rotational block comprises at least one first rotationalstopper and at least one second rotational stopper, the first rotationalstopper and the second rotational stopper abutting against one anotherin the end position of the dosage setting member, wherein the at leastone first rotational stopper is mounted, secured against rotating, bythe dosage setting member and the at least one second rotational stopperis mounted, secured against rotating, by the drive device.
 6. Theadministering apparatus of claim 1, wherein the rotational blockcomprises at least one first rotational stopper and at least one secondrotational stopper, the first rotational stopper and the secondrotational stopper abutting against one another in the end position ofthe dosage setting member, wherein the at least one first rotationalstopper is formed, secured against rotating, by the dosage settingmember and the at least one second rotational stopper is formed, securedagainst rotating, by the drive device.
 7. The administering apparatus ofclaim 1, wherein the rotational block comprises at least one firstrotational stopper and at least one second rotational stopper, the firstrotational stopper and the second rotational stopper abutting againstone another, wherein the at least one first rotational stopper is formedby the dosage setting member and the at least one second rotationalstopper is connected, secured against rotating, to the driven device. 8.The administering apparatus of claim 7, wherein the at least one secondrotational stopper cannot be moved axially relative to the translationalstopper.
 9. The administering apparatus of claim 1, wherein therotational block comprises at least one first rotational stopper and atleast one second rotational stopper, the at least one first rotationalstopper and the at least one second rotational stopper abutting againstone another in the end position of the dosage setting member, whereinthe at least one first rotational stopper and the at least one secondrotational stopper protrude axially towards each other.
 10. Theadministering apparatus of claim 9, wherein the at least one firstrotational stopper and the at least one second rotational stopper areeach formed on one of two abutting areas which face one another axially.11. The administering apparatus of claim 1, wherein the rotational blockcomprises at least one first rotational stopper and at least one secondrotational stopper, the at least one first rotational stopper and the atleast one second rotational stopper abutting against one another in theend position of the dosage setting member, wherein the at least onefirst rotational stopper is formed as a protrusion and the at least onesecond rotational stopper is formed as a recess, the protrusionprotruding into the recess to block the second rotational dosingmovement.
 12. The administering apparatus of claim 1, wherein therotational block comprises at least one first rotational stopper and atleast one second rotational stopper, the at least one first rotationalstopper and the at least one second rotational stopper abutting againstone another in the end position of the dosage setting member, whereinthe at least one first rotational stopper is formed as a unitary piecewith the dosage setting member and the at least one second rotationalstopper is formed as a unitary piece with the at least one translationalstopper.
 13. The administering apparatus of claim 1, wherein the dosagesetting member comprises a thread and the driven device comprises athread, the engagement between the dosage setting member and the drivendevice being a threaded engagement of the dosage setting member threadand the driven device thread about the translational axis.
 14. Theadministering apparatus of claim 1, wherein the rotational blockcomprises a plurality of first rotational stoppers and a plurality ofsecond rotational stoppers, the plurality of first rotational stoppersand the plurality of second rotational stoppers abutting against oneanother in the end position of the dosage setting member, each of theplurality of first rotational stoppers forming a pair of stoppers witheach one of the plurality of second rotational stoppers, wherein theeach pair of stoppers thus formed is arranged adjacently, spaced fromone another in the circumferential direction.
 15. The administeringapparatus of claim 1, wherein a cannula of at most 30 gauge forms aninjection or infusion cannula of the administering apparatus.
 16. Theadministering apparatus of claim 1, wherein a cannula exhibiting acombination of outer and inner diameter not specified in ISO 9626,having an outer diameter of 320 μm at most and as thin a wall thicknessas possible fors an injection or infusion cannula of the administeringapparatus.
 17. The administering apparatus of claim 16, wherein thecannula is a 31 gauge cannula.
 18. The administering apparatus of claim16, wherein the cannula is a 32 gauge cannula.
 19. A reservoir modulefor an administering apparatus, said reservoir module comprising: a) afront casing section of the administering apparatus, the front casingsection including a reservoir for a fluid product; b) a pistonaccommodated in the reservoir such that it can move in an advancingdirection towards an outlet of the reservoir, the piston delivering theproduct; c) a piston rod for acting on the piston; d) a drive devicecoupled to the piston rod to move the piston rod in the advancingdirection; e) a dosage setting member coupled to the piston rod suchthat the piston rod and the dosage setting member slave one another inthe advancing direction, the dosage setting member and the piston rodperforming a rotational dosing movement about the translational axis,the rotational dosing movement effecting an axial, translational dosingmovement of the piston rod relative to the driven device and the frontcasing section; f) a translational stopper for limiting movement of thepiston rod and the dosage setting member in the advancing direction, thedosage setting member abutting against the translational stopper in anaxial end position of the dosage setting member; and g) a rotationalblock which, in the end position of the dosage setting member, permitsthe rotational dosing movement in a first rotational direction andblocks the rotational dosing movement in a second rotational direction,the dosage setting member being moved away from the translationalstopper by the permitted rotational dosing movement.
 20. The reservoirmodule of claim 19, wherein the rotational block comprises at least onefirst rotational stopper and at least one second rotational stopper, theat least one first rotational stopper and the at least one secondrotational stopper abutting against one another in the end position ofthe dosage setting member, wherein the at least one first rotationalstopper is mounted, secured against rotating, by the dosage settingmember and the at least one second rotational stopper is mounted,secured against rotating, by the casing.
 21. The reservoir module ofclaim 19, wherein the rotational block comprises at least one firstrotational stopper and at least one second rotational stopper, the atleast one first rotational stopper and the at least one secondrotational stopper abutting against one another in the end position ofthe dosage setting member, wherein the at least one first rotationalstopper is formed, secured against rotating, by the dosage settingmember and the at least one second rotational stopper is formed, securedagainst rotating, by the casing.
 22. The reservoir module of claim 19,wherein the rotational block comprises at least one first rotationalstopper and at least one second rotational stopper, the at least onefirst rotational stopper and the at least one second rotational stopperabutting against one another in the end position of the dosage settingmember, wherein the at least one first rotational stopper is mounted,secured against rotating, by the dosage setting member and the at leastone second rotational stopper is connected, secured against rotating, tothe piston rod.
 23. The reservoir module of claim 22, wherein the atleast one second rotational stopper cannot be moved axially relative tothe translational stopper.
 24. The reservoir module of claim 22, the atleast one second rotational stopper comprising a blocking device mountedby the front casing section such that it cannot move axially but canrotate about the translational axis, the blocking device beingconnected, secured against rotating, to the piston rod and in securingengagement with the piston rod, the blocking device substantiallypreventing the piston rod from moving counter to the advancing directionor at least makes this more difficult.
 25. The reservoir module of claim19, wherein the front casing section forms a blocking device, theblocking device being in securing engagement with the piston rod andsubstantially prevents the piston rod from moving counter to theadvancing direction.
 26. The reservoir module of claim 19, wherein thefront casing section mounts a blocking device such that it cannot moveaxially, the blocking device being in securing engagement with thepiston rod and substantially prevents the piston rod from moving counterto the advancing direction
 27. The reservoir module of claim 19, whereinthe front casing section comprises a sleeve-shaped reservoir portioncomprising the reservoir and a sleeve-shaped mechanism holder forholding the piston rod, the sleeve-shaped reservoir portion and thesleeve-shaped mechanism holder being separately formed.
 28. Thereservoir module of claim 27, wherein the sleeve-shaped reservoirportion and the sleeve-shaped mechanism holder are unreleasablyconnected to one another.
 29. The reservoir module of claim 19, whereinthe reservoir module is a disposable module configured to be exchangedin its entirety once the reservoir has been emptied.